-norton



(No Model.) 2 SheefisSheet 1.

L. S.-NORTO1\ & F. E. HOFFMAN, TELETHERMOMETEE.

No. 493,558. ate ted Mar. 14, 1893.

(No Model.)

V V dtnassw L.-S. NORTON & F. E. HOPFM TELETHBRMOMETER.

Patented Mar. 14, 1893..

2 Sheets-Sheet 2. AN.

lK/fm 7L In en Z-ors,

UNITED STATES PATENT OFFICE.

LEROY S. NORTON AND FRANK E. HOFFMAN, OF ALPENA, MICHIGAN; SAID HOFFMAN ASSIGNOR TO SAID NORTON.

TELETHERMOMETER.

SPECIFICATION forming part of Letters Patent No. 493,558, dated March 14, 1893.

Application filed October 31, 1892- Serial No. 450,466. (No model.)

To aZZ whom it may concern: ture extending from 40 to 70, with an alarm Be it known that we, LEROY S.NORTON and wire arranged to make contact at 80. FRANK E. HOFFMAN, citizens of the United In Fig. 2 we have shown the wires arranged States, residing at Alpena, in the county of to make contact with the mercury at intervals 55 5., Alpena and State of Michigan, have invented of but it is obvious that by using more certain new and usefulImprovementsin Telewires they may be arranged to make contact thermometers, of which the following is a at each degree, or at intervals of two, three, specification. four or any number of degrees desired. Hav- Our invention relates to apparatus for asing provided the requisite number of these 60 1o certaining at will the temperature, within thermometers thus provided with contact specified limits, in aseries of rooms or places, wires, we place one in each of the occupied and indicating the same to the janitor or perrooms, as shown in the rooms A and B F1g. son in charge at any desired central point; 1, and extend the wires on to an indicator 1, and the invention consists in a novel combilocated at the desired point, usually in the 65 nation and arrangement of devices or parts basement, or wherever the janitor or person for that purpose, as hereinafter more fully in charge can have ready access to the same, set forth. this indicator being connected by a wire 19 to Figure 1 is transverse Vertical section of a the positive pole of an ordinary open circuit building showing the invention arranged for battery a, as shown in Fig. 1.there being 70 :0 operation therein. Fig. 2 is an enlarged face also a return wire '11. connected with the bulb 4 View of a portion of the apparatus, to more or lower portion of the thermometer tubein clearly illustrate its construction and mode the same manner as the wires m, and which of operation; and Figs. 3, 4 and 5 are face is connected to the opposite or negative pole views of modified forms of certain parts'of of the battery as also shown in Flg. 75 2 5 the apparatus. In the line of each wirem there is inserted The object of this invention is to provide a a spring key or push button 0, as shown in cheap and simple means by which the janitor Figs. 1 and 2, these being so arranged as to 01 person in charge of a building can at any normally remain open, and to complete the time ascertain the temperature in any and line or circuit only when pressed. 71th the Se all of the rooms of the building, without leavparts thus arranged, it will readily be seen, ing his room or position. To accomplish this that by simply passing the thumb or fingers result, we place in each of the rooms, or in as over these keys successively, or by pressing many of them as may be desired a thermomeon them all at once, the circuit will be comter T, as shown in Fig. 1. These thermomepleted through such of the wires m as have 85 ters, as shown more clearly in Fig. 2 have the been brought into contact with the mercury ends of a series of electric conducting wires in the thermometer tube, thereby operating in m fused tightlyinto the side of the tube which I the indicator the correspondingly numbered contains the mercury, the ends of the wires cards or plates, and thus indicating the h ghpassing through the wall of the tube, so that est point to which the temperature has risen 90 as the mercury therein rises by expansion it within the room where the thermometer is 10- will come in contact successively with the cated. several wires, whatever their number may be. In order to ascertain the temperature in As the temperature of rooms occupied by each room separately, each setotwires m for scholars or other persons is usually kept at the difierent rooms will be provided with a 5 5 from to Fahrenheit, it is sufficient for set of keys, as shown in Fig. 1.

ordinary purposes to so arrange these wires In order to call attention in case the temas to indicate the temperature within those perature should become excessive, and the extremes; but it is obvious that they may be person in charge should be negligent or abarranged to indicate a much greater range of sent from his post, we extend what we term I00 50 temperature, and in Fig. 2 we have shown the maximum or alarm wire on to the bat them arranged to cover a range of temperatery separately, and place in the line of said wire an electric bell b, as shown in Figs. 1 and 2, so that whenever the mercury in the tube makes contact with this wire the bell will be rung automatically. In Fig. 2. we have shown this arranged to make contact at 80, but it is obvious that it may be arranged at any point desired above the normal temperature at which it is desired to keep the room. Another advantage of this is that it will serve as a fire alarm, and for such purpose it may be arranged to ring a larger bell located outside of the building, or be connected with the fire alarm of the city, or with the fire engine stations, or both, at will. A minimum wire and bell may be also added if desired.

There are many forms of temperature indicating devices which may be used in lieu of the thermometers T, and be made to operate the same. In Fig. 2, E indicates a metallic bar or rod of a kind that has a highdegree of expansibility. having one end permanently fastened in place by a stud 0 or any suitable means, and having at its opposite and free end a series of teeth arranged to engage with a pinion t mounted on a shaft to which is secured a hand or pointer H, the outer end of which has frictional contact with'a series of insulated metallic plates 6, each of these plates being provided with a binding screw for connecting the wires m, as shown. The expansion and contraction of the bar E will cause the hand or pointer H to move and thus successively make contact with the plates 6, so that by pressing the keys or buttons 0 in the lines m, the circuit will be completed and the temperature shown at the indicator I, the same as when themercurial thermometers are used, as above described. In order to hold the rack of the expansion barE in gear with the pinion t, and permit it to move freely, a friction roller 1' is arranged to bear against its rear side, as shown in Fig. 3. In Fig. 4, we have shown a similar series of insulated metallic plates e arranged in a right line, with an expansion bar E provided with a contact point arranged to rest and slide to and fro on the plates e, as the bar expands and contracts, the

wires m being connected one to each separate plate, the same as in Fig. 2, the arrangement of the keys, indicator and alarm bell being the same as previously described.

In Fig. 5 R indicates an air tight vessel of any suitable kind to be filled with air, gas or volatile fluid expansible by heat. connected a benttube T partially filled with mercury, and having the wires m inserted in others are the equivalents of the thermometer T, and obviously may be substituted therefor in our apparatus without changing its princlpleor mode of operation.

To this is For the more ready illustration of our in vention, we have shown each wire as being run separately from the thermometer to the indicator, but as is well known by all electricians, the wires if properly insulated may, for each room be bunched or twisted into a cable; and they will preferably be concealed to prevent being broken or injured by ch11- dren or others.

While we have shown an ordinary battery as the source of electricity, it is obvious that the same result will be obtained with a suitable current produced by other means. It is also obvious that the indicator instead of being located within the building, may be located at any other point, wherever desired, and be made to operate the same; and that if desired, one or more additional indicators may be located elsewhere, and thus by s1mply connecting these additional indicators with the circuit, the temperature may be s1- multaneously indicated at as many dlfierent points as may be desired; any one familiar withelectrical matters being able to make the necessary connections for this purpose, and which it is therefore unnecessary to show.

The apparatus is exceedingly simple and cheap, and can be applied by any person familiar with electrical devices; and as the line is open at all times except when the keys are pressed, the exhaustion of the battery is very slight indeed, thus rendering the apparatus durable and requiring but little attention.

Having thus described our invention, what we claim is- 1, An apparatus for indicating the temperature of one or more apartments, comprising the following elements in combination: a thermometer in the apartment or apartments, provided with contact points corresponding with the degrees of temperature to be indicated; an indicator provided with a series of signals corresponding with the several contact points of the thermometer; electric conductors connecting the contact points of the thermometer with the signals of the indicator, each of said conductors being provided with a contact key or button arranged to normally keep the line or circuit open; a battery or source of electrical energy; and a return wire connecting the thermometer and the battery, substantially as shown and described.

2. In combination with two or more compartments, thermometers, one in each compartment, each thermometer provided with a series of contact points corresponding to different degrees of temperature; an indicator provided with signals corresponding to the respective contact points of said thermometers; conductors connecting the respective contact points of the thermometers with the corresponding signals of the indicator, each of said conductors being provided with a key or switch to complete its connection or circuit; a battery or source of electrical energy; a return conductor connecting the thermostats with the battery; and a separate conductor ICC the thermometers with the corresponding signals of the indicator; a source of electrical energy, and a series of circuit closing keys or devices, arranged to complete the circuit between the contact points of the thermometers and the indicator signals at will.

In witness whereof we, hereunto set our hands in the presence of two witnesses.

LEROY S. NORTON. FRANK E. HOFFMAN. Witnesses:

J OSEPH W. FITZGERALD, ALEX. MoDoNALD. 

